The California Supreme Court on Wednesday agreed to decide whether proponents of Proposition 8, California's gay marriage ban, have legal standing to defend it in court, the AP reported.

Last month, the U.S. 9th Circuit Court of Appeals asked the high court to intervene on the question of standing.

The justices met behind closed doors to decide whether to hear arguments.

After a federal judge in San Francisco declared the law unconstitutional, proponents of the 2008 ballot measure appealed the ruling.

But the named defendants in the case – Arnold Schwarzenegger, as governor, and Governor Jerry Brown, as attorney general – refused to defend the law in court, prompting ProtectMarriage.com, the conservative group that put Proposition 8 on the ballot, and Imperial County, to step in.

The three-judge appeals panel heard oral arguments in the case in December. The court said it “cannot consider this important constitutional question” until it resolves the issue of legal standing, and asked the high court to rule on the matter.

The unforeseen detour will slow down the case considerably; the court isn't expected to hear oral arguments until September, at the earliest.

Backers of the law have responded with legislation. California State Senator Tom Harman's Defense of Initiative Statutes would compel the state attorney general to defend ballot measures in court.

“Yes on 8 and their cohorts in the Legislature know that current law doesn't allow them to appeal,” Geoff Kors, executive director of Equality California, said in an email to supporters. “That is why they are trying to change the law.”

Democratic Attorney General Kamala Harris has vowed not to defend Proposition 8 in court.